MAX8738 Datasheet, PDF (1/13 Pages) Maxim Integrated Products – EEPROM-Programmable TFT VCOM Calibrator with I2C Interface

19-3624; Rev 0; 3/05
EVAALVUAAILTAIOBNLEKIT
EEPROM-Programmable TFT VCOM
Calibrator with I²C Interface
General Description
The MAX8738 is an I²C-programmable VCOM-adjust-
ment solution for thin-film transistor (TFT) liquid-crystal
displays (LCDs). The MAX8738 simplifies the labor-inten-
sive VCOM-adjustment process and replaces mechani-
cal potentiometers, which significantly reduces labor
costs, increases reliability, and enables automation.
The MAX8738 attaches to an external resistive voltage-
divider and sinks a programmable current to set the
VCOM voltage level. An internal 7-bit digital-to-analog
converter (DAC) controls the sink current. The DAC is
ratiometric relative to AVDD and is guaranteed to be
monotonic over all operating conditions. This VCOM
calibrator IC includes an EEPROM to store the desired
VCOM voltage level. The EEPROM can be programmed
repeatedly, giving TFT LCD manufacturers the flexibility
to calibrate the display panel as many times as the
manufacturing process requires.
The MAX8738 features a 2-wire I²C* interface for DAC-
adjustment commands and EEPROM programming.
The interface utilizes the existing I²C bus on the LCD
panel connector so no additional panel connector pins
are required. The MAX1512 is a similar product with a
1-wire interface and is recommended for applications
with no existing I²C interface.
The MAX8738 is available in an 8-pin µMAX^® package.
A complete evaluation kit is available to simplify evalua-
tion and production development.
Features
♦ 7-Bit Adjustable Sink-Current Output
♦ Resistor-Adjustable, Full-Scale Range
♦ Guaranteed Monotonic Output Over Operating
Range
♦ 2-Wire I²C Interface
♦ EEPROM Stores VCOM Setting
♦ 4.5V to 20V Analog Supply Voltage Range
(V_AVDD)
♦ 60µA (max) AVDD Supply Current
♦ 16.1V to 28V EEPROM Programming Supply
Voltage Range (V_HV)
♦ <1µA HV Supply Current (Not in Program Mode)
♦ 8-Pin µMAX
Ordering Information
PART
TEMP RANGE
MAX8738EUA
-40^oC to +85^oC
MAX8738EUA+
-40^oC to +85^oC
+Denotes lead-free package.
PIN-PACKAGE
8 µMAX
8 µMAX
LCD Panels
Notebook Computers
Display Products
LCD TVs
Applications
µMAX is a registered trademark of Maxim Integrated Products, Inc.
Pin Configuration
TOP VIEW
OUT 1
AVDD 2
V_DD 3
GND 4
MAX8738
8 SET
7 SCL
6 SDA
5 HV
µMAX
Typical Operating Circuit
+3.3V
VGON
V_DD
HV _AVDD
AVDD
SDA
I²C
BUS
R1
MAX8738
SCL
OUT
R2
GND
SET
R_SET
VCOM
Purchase of I²C components from Maxim Integrated Products,
Inc., or one of its sublicensed Associated Companies, conveys
a license under the Philips I²C Patent Rights to use these com-
ponents in an I²C system, provided that the system conforms
to the I²C Standard Specification as defined by Philips.
________________________________________________________________ Maxim Integrated Products 1
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at
1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.